(1) Field of the Invention
This invention relates to three-wheeled vehicles and particularly to three-wheeled vehicles that tilt when making turns.
(2) Description of the Prior Art
As the cost of petroleum products continues to rapidly increase, the need for cheaper means of transportation becomes more imperative. The replacement of four-wheeled vehicles with two-wheeled or three-wheeled vehicles as a means of achieving increased economy of operation, although readily apparent, has not achieved deserved acceptance primarily because of the safety hazards associated with the operation of two-wheeled and three-wheeled vehicles. The stability of two-wheeled vehicles, because of their two point contact with the ground, is much less than that which can be achieved with three-wheeled vehicles. However, three-wheeled vehicles, in most instances, are merely modified two-wheeled vehicles whereby a side car is attached as an adjunct to the basic two-wheeled vehicle. This arrangement is not entirely satisfactory because of asymmetric load and handling characteristics. To improve the stability of three-wheeled vehicles prior art discloses that a two-wheeled forebody section which forms the front part of the vehicle is coupled at its rear to the front of a standard two-wheeled motorcycle from which the front fork and front wheels have been removed. In another disclosure two front wheels are not only coupled to a motorcycle frame by means of parallelogram-type wheel support assembly, but means are also provided whereby an operator may apply a stabilizing force to effect a desired banking, or upright, posture for the operator and the frame while maintaining all three wheels at the same angle with respect to the ground. The former arrangement has not been entirely satisfactory because the frame cannot be banked in unison with one or more of the wheels and the latter arrangement also has not been entirely satisfactory for it requires the intervention of the operator to apply such stabilizing force.